Semiautomatic telegraphic sending machine



Jan. 14, 1941. 14. G. MARTIN 2,228,470

SEMIAUTOMATIC TELEGRAPHIC SENDING MACHINE Filed May 11, 1940 2 Sheets-Sheet l BY i ay/ 7:24AM

7 ATTO NEY 7 Jan. 14, 1941, M -rm 2,228,470

SEMIAUTOMATIC TELEGRAPHIC SENDING MACHINE Filed May 11, 1940 2 Sheets-Sheet 2 Patented Jan. 14, 1941 PATENT OFFICE SEMIAUTOMATIC TELEGRAPHIO SENDING MACHINE Horace G. Martin, Brooklyn, N. Y.

Application May 11, 1940, Serial No. 334,485

14 Claims.

This invention relates to semiautomatic telegraph instruments for transmitting messages by dash and dot commonly known as the Morse code, or similar signals, and particularly to an improvement on the instrument disclosed in my U. S. Letters Patent #2,148,028.

The ordinary Morse key requires a movement of the hand for each dash and dot. This is extremely tiresome and wearing on the muscles and nerves of the operator, particularly when the dots predominate as they do in the Morse code. Vibratory devices have been introduced whereby the key requires only one movement, to automatically produce a series of signals such as dots. Such devices, however, have the drawback that they always necessitate the starting of a series of vibrations for each letter or numeral and an effort is required to overcome the natural tendency of the vibrator to lag when the key is go thrown over to produce the desired series of vibrations.

Moreover, to produce just such series of vibrations that will result in the desired number of dots by the throw of the key requires a certain adjustment according to the special touch and skill of the operator. As a result of such individual adjustment the instrument can be used only by the particular operator, and a new adjustment would be necessary for any other operator. Not only that, but if the particular operator is call-ed upon to transmit a message from a different position in the operating room than that usually occupied by him, he is obliged to bodily carry his own instrument over to the new position, which entails loss of time due to the necessity of disconnecting and connecting the apparatus.

Furthermore the instrument of the known type generally includes as a unit the vibrator, adjusting mechanism and many parts which require finishing and polishing, whereby the instrument is rendered quite costly.

The main object of my invention is to provide a constantly impelled signal transmitting device which either may be used in connection with the key operated circuit closing means as a complete unit, .or may be constructed as a separate unit to serve as a master transmitter for a plurality of key operated circuit closing means.

When using a constantly impelled signal transmitting device, such as the one disclosed in my said Letters Patent #2,148,028, it may happen that on closing the circuit by the key lever a signal smaller than the normal, such .as a spit dot, 55 will betransmitted'which must be prevented. It

is, therefore, another object of this invention to provide means whereby the closing of the circuit through the constantly impelled signal transmitting device by the operation of the key lever will be automatically and momentarily retarded until a complete normal signal can be transmitted.

. My improved instrument may be constructed for transmitting only dots, or only dashes, or both.

To accomplish my objects I provide a manually operable mechanism for closing the circuit, and a transmitter including a contact member adapted to be in continuous uniform motion and which is capable of automatically and alternately make and break the circuit and produce a series of predetermined signals when the key is thrown to close the circuit.

In practice the constantly moving signal transmitting mechanism may consist, for instance, of a motor or otherwise impelled rotor having on its circumference a series of equidistantly spaced contact segments cooperating with a stationary contact element which is conductively connected to the key operated circuit closing means. 5

This constantly moving device may be either applied to and form a unit with the key portion of the apparatus or be constructed as a separate unit to be mounted at any suitable place remote from the operating place and capable of serving 30 as a master transmitter for a number of operators simultaneously.

As means for automatically retarding the closure of the circuit by the key lever, an electric magnet or the like may be employed which will 35 be energized by a circuit passing through the contact segments of said rotor and which electromagnet may affect the key lever so that while the stationary contact cooperating with the rotor is passing over a contact segment of the latter this key lever cannot be moved into closing position. The operator desiring to send a message, say dots during that instant will feel the drag on the key lever occasioned by the magnetic force and will be permitted to move the key into closing position as soon as the stationary contact finger passes onto the next contact segment of the rotor.

With my new instrument the closing of the circuit to transmit a series of impulses is effected by a slight or what I call a feather touch of the key lever, rather than the snappy touch produced by fingerand wrist movements as in the old style instruments and which depend upon the individual operators peculiar technique and skill.

The magnetic drag on the key lever is compensated by the new technique of feather touch and has the advantage of preventing the running together of characters, which, with the 01d type of instruments, by failing to allow enough time between the side swings of the key, is apt to happen. The slight holding back until starting a new signal, which is of such small fraction of time as to be hardly measurable, thus affords proper spacing between characters.

My invention will be more clearly understood by reference to the accompanying drawings which constitute part of this specification and in which similar reference characters denote corresponding parts.

Figure 1 is a top plan view of the telegraph transmitting instrument according to my invention;

Figure 2 is a cross section on line 22 of Figure 1;

Figure 3 is a top plan view of a modified con struction of my telegraph transmitting instrument;

Figure 4 is a longitudinal section on line 44 of Figure 3;

Figure 5 is a top plan View of a modified construction of the key lever mechanism and Figure 6 is a diagrammatic view of a master transmitter and a plurality of individually operable telegraph instruments in electric connection therewith.

Referring in detail to the drawings, IEJ denotes the usual iron base supported on insulating feet II. l2 denotes a frame, or boss projecting upwardly from and fixed to the base Fig. 4. This boss serves as a support for the key mechanism, which comprises two metal levers I 3, I 4 extending longitudinally of the base in opposite directions and formed with disk shaped portions I300, I411 adapted to bear upon one another by means of a ball bearing or the like (Figure 4) Attached to lever I3 which extends rearwardly is a handle l5 carrying a thumb piece I6 and an electric contact point I I which in cooperation with an adjustable stationary contact point I8 provided in the post I9 serve to close the electric circuit for the transmission of dashes. The second forwardly extending lever I4 is formed at its rear with an extension I4b displaced laterally relative the lever I3 and serving as an abutment. The two disk shaped portions i3a, I ia are centered on the boss I2 by a vertical headed bolt or pin which projects through central bores thereof and through a vertical bore provided in the boss I2. The lower end of said bolt or pin 20 projects into a recess Ida. provided in the bottom of the base IE3 and may be screw threaded to receive a nut 2|. A set screw 2| projecting through a bore in the abutment I4b of the lever I4 and fixed to the lever I3 carries a coil spring 22 which bears at one end against a nut 23 working on said screw 2i and at the other end against said abutment I4b. This spring is adapted to normally hold the lever I3 against said abutment. Provided on said abutment is a contact point 24 which is adapted to cooperate with an adjustable contact point 25 provided in the post 25 which contact points constitute a manually operated switch controlling the circuit serving for the production of dot signals. The forward end of the lever I4 is provided with a projection 21 which serves as armature for an electromagnet 28 or the like the function of which will be hereinafter described. 29, 2S denote the posts for the external electric line connections.

With the American Morse code the dashes are of difierent lengths to transmit letters T, L and 0 (zero) while with the International code as used in wireless and radio telegraphing the transmission of both dash and dot signals may be automatic, as will be hereinafter shown.

In the modification shown in Figs. 1 and 2 which is designed for the American Morse code the transmission of dashes is accomplished in the usual way, i. e. through closing the circuit by throwing the key operated lever I3 to the left and holding the contact point I'I against the stationary contact point I8 until the dash of the desired length has been transmitted.

The means for automatically transmitting im-' fixed to the base Ill and a stationary spring actuated contact member 36. This drum or rotor 3!) may be constantly impelled by an electric motor 33 through worm gears 34, 35 or in any other suitable manner. The motor 33 may be driven through an electric source (not shown). The drum 30 on its circumference is provided with a series of equidistantly spaced contact segments 38a suitably insulated from one another and is in continuous contact with said contact member 36. This rotor 39 in cooperation with said contact member constitutes an automatic circuit make and break mechanism through the operation of which signals such as dots are automatically transmitted and which I, therefore, in the following, shall term automatic impulse transmitter.

The electromagnet 28 is adapted to be energized from an electric source, which may be the same as that which actuates the motor 33 as shown in this modification, or from a separate battery. The function of the electromagnet 28 is to retard the closing of the line circuit while at the instant the operator is to send the message the contact member 36 happens to be in contact with any one of the contact segments 30a of the rotor 30. The circuit which energizes the electromagnet may be automatically, controlled through a switch 37. This switch 31 comprises a resilient contact member 37a and a fixed contact member 37b, the resilient contact member being adapted to be actuated by the lever I4. One wire leading from the motor or battery circuit is connected to one pole of the electromagnet 28 while the other wire is connected to the element 36, the resilient member 31a being conductively connected to the rotor 30 and the fixed member 3% of the switch 31 to the opposite pole of the electromagnet 28. While the lever I4 is in normal position, i. e. in the position where contacts 24, 25 are open, and the armature 2] rests against the electromagnet 28, the switch 31 is closed. During the operation of the rotor 30 its contact segments will alternately close and open the auxlliary circuit of the motor or battery which passes through the electromagnet 28 and as a result thereof the arm I4 will be alternately attracted and released. When while the arm is attracted the operator attempts to swing the key lever I3 to the right, he will feel the drag on'the'lever I4 held by magnetic force against the electromagnet 2B and will, therefore, have to wait until the stationary contact 36 passes onto an insulation. At

that instant the lever I4 is released, and the operator will be above to move the lever I3 to the right to close the contacts 24, 25. By so doing the forward end of arm I 4 will be swung away from the electromagnet 28, simultaneously opening the switch 3? and the circuit through the electromagnet. The operator will hold the key lever in the line closing position, until the automatic transmitter has transmitted the particular number of dots or signals desired.

When the instrument is to be used, the rotor 38 is set into motion by closing a manual electric switch (not shown). When swinging the lever E3 to the left to produce dashes, the arm I4 remains stationary. p

In the modification shown in Figure 3 the instrument-is constructed for the automatic transmission of both dot and dash signals. The general principle and arrangement is the same as in the modification shown in Figure 1. Here two separate keys l3, M are employed, which are mounted on the boss l2 in superposed position, as in the first modification. They are provided with forwardly extending arms I3 I4 respectively, each formed with a metal projection 21 acting as armature of a corresponding electromagnet 23. The circuits energizing the said electrcmagnets may be derived from a battery B or, as in the first modification, from the source operating the motor 33, and may be automatically controlled by switches 31a, actuated by the arms 83 M in the aforedescribed manner. The transmission of both dash and dot signals is accomplished automatically on closing the line circuit of the corresponding key lever l3, I4.

For the automatic transmission of the signals I may use a single rotor 38, which like rotor 39 is mounted on the spindle 3| constantly driven from the motor 33, and whose circumference isv provided with two parallel rows of contact seg-- ments 38a, 38b suitably insulated from one another and cooperating with corresponding staticnary contact members 36a, 36b.

The disk shaped portions 13a and Ma of the levers 13', M are superposed and may be borne on one another on the boss I2 in the same manner as in the first modification and as shown in Figure 4.

Instead of using two separate keys H3, M the construction may be modified as shown in Figure 5. Here one of the superposed disk shaped portions Ma, Ma has yieldingly fixed to it as at 39c a key lever 39 which extends rearwardly and longitudinally of the base andto which are attached the handle and finger piece IE, IS. This arm or lever 39 carries the contacts I! and 24 which are adapted to cooperate with the stationary contacts l8 and 25 respectively. Each disk provided with a rearwardly extending abut-' ment E30, M respectively, so that when the key lever 39 is swung to the left the dash contacts ii, is will close the electric line circuit, and when the key lever is swung to the right the dot contacts 2d, 25 will close the electric line circuit. By the movement of the key lever 39 to the left or right, it will, in acting against either of the respective abutments I30, ic, turn the corresponding disk ltd, Ma on its pivot 20. Projecting forwardly from the disks are the arms I3 M which carry the armatures El for the respective electromagnets.

The operation of the construction shown in Figures 3 and is as follows:

With the key levers l3, H3 or key lever 39 in normal position, the arms I3 I4 will bear with their metal projections close to or rather against the electromagnets 28, In this position the switches 31a will be closed so that whenqthe rotor 38 is set into motion the battery circuit will cause each of the electromagnets 23 to be alternately energized and disenergized, as the stationary contarct 36a, 3% pass alternately from the contact segments 38a, 38b respectively onto the insulations between them. When energized the electromagnets will attract the respective armatures and lock the arms I3 M in their normal positions. Just as soon as the electromagnets are disenergized the arms I3 I4 are released and the key levers l3, M or the key lever 39 can be swung to close the contacts for the dash or dot signals as the case may be.

The constantly impelled signal transmitter may be employed as a master transmitter for a number of key lever instruments, whereby the construction of the latter will be greatly simplified and their cost considerably reduced. The master transmitter may be used for either dots alone or dots and dashes. In the modification shown in Figure 6 the automatic dot transmitter is shown as consisting of the motor driven rotor 30 formed circumferentially with contact segments 30a and cooperating with the stationary contact member 36. The automatic dot transmitter being a separate unit, may be mounted at any suitable place remote from the key operated circuit closing units 4B, 40', 48 etc. Each key unit may comprise a metal base I0 and lever mechanism l3, M with circuit closing contacts I 'l, l8 and 24, and electric connections similar to the construction shown in Figure 1. For retarding the closing of the line circuits, while the contact member 36 slides over a contact segment of the rotor each key lever mechanism may be automatically controlled by an electromagnet 28 energized from av separate circuit which is controlled by a switch 311) similar to the switch 31 or 3111 and actuated by the arm I 4.

4|, 4!, M etc. denote the conventional electric sounders included in each line circuit for the v respective key mechanisms 48, Ml, 42, etc.

The operationof the instruments shown in this modification is clear from the foregoing description.

Various other modifications may be made in the construction of the instrument according to my invention without departing from the principle thereof. I, therefore, do not wish to restrict myself to the details described and shown.

What I claim is:

1. In a semiautomatic telegraphic sending instrument, an electric circuit, a key operated electric switch for controlling said circuit, an automatic impulse transmitter including a constantly impelled circuit make and break mechanism having a plurality of uniformly spaced contact ele-.

'ments, electric connections between said key operated switch and said constantly impelled mechanism and means affected by said constantly impelled mechanism and in its turn adapted to affect said key operated switch, so as to temporarily retard the closing of said switch and prevent the transmission of an incomplete signal.

2. In a semiautomatic telegraphic sending instrument, an electric circuit, a key operated.

switch therefor, an automatic impulse transmitter including a constantly impelled circuit make and break mechanism having uniformly spaced contact elements, electric connections between said key operated switch and said constantly impelled mechanism and means for automatically and temporarily retarding the operation of said key operated switch, to prevent the transmission of an incomplete signal, said last named means including electric means afiected by said constantly impelled make and break mechanism and in its turn adapted to afiect the operation of said key operated switch While the latter are out of circuit closing position.

3. In a semiautomatic telegraphic sending instrument, an electric circuit, a key operated circuit switch therefor, an automatic impulse transmitter including a constantly impelled member having a plurality of uniformly spaced contact elements and a stationary member cooperating with the latter, electric connections between said key operated switch and said impulse transmitter and electric means affected by said impulse transmitter and adapted to retard the operation of said switch, while there is conductive contact between said constantly impelled member and said stationary contact.

4. In a semiautomatic telegraphic sending instrument, an electric circuit, a. key lever actuated switch for controlling said electric circuit, an automatic impulse transmitter including a constantly driven rotor having a plurality of uniformly spaced electric contacts, a stationary contact member cooperating with said rotor, electric connections between said transmitter and said switch, an electromagnet whose armature forms part of said key lever actuated switch and an electric circuit for energizing said electromagnet and controlled by said impulse transmitter so that while there is conductive contact between any of its contacts and said stationary contact, said electromagnet will attract and lock said key lever switch out of circuit closing position.

5. In a telegraphic sending machine, according to claim 4 in which said key operated switch includes a lever formed with a projection at its forward end adapted normally to bear against said electromagne-t and serve as its armature.

6. In a semiautomatic telegraphic sending instrument, an electric circuit, key operated switches for controlling said circuit, one for the dash and one for dot signals, constantly impelled automatic impulse transmitters for both said means, electric connections between each of said key operated switches and said automatic transmitters, and an electromagnet for each of said switches affected by said automatic transmitter and whose armature affects each of said switches, so as to temporarily retard the closing of the circuit by either one of them and prevent the transmission of incomplete signals.

7. In a semiautomatic telegraphic sending instrument according to claim 6 in which said switches include two. separate independently movable key levers, each having a forwardly extending arm carrying an armature for the corresponding electromagnet.

8. In a semiautomatic telegraphic Sending instrument according to claim 6 in which said constantly impelled signal transmitters comprises a common rotor formed with two insulated different series of uniformly spaced contact segments, and stationary contact members cooperating with said contact segments.

9. In a semiautomatic telegraphic sending instrument according to claim 4 in which a switch is provided to automatically control the circuit through said electro-magnet, by the movement of said key operated mechanism.

10. In a semiautomatic telegraphic sending instrument according to claim 6 in which said key operated switches include a common key adapted to cooperate with stationary contacts and two independently movable contact bearing elements adapted to be operated from said single key.

11. In a semiautomatic telegraphic sending instrument, an electric circuit, a plurality of key operated units including switches for controlling said circuit, a constantly impelled circuit make and break mechanism having uniformly spaced contact points and capable of acting continuously as a source of signals and serving as master signal transmitter for all said units, said master transmitter being remote and separate from said key operated unit, whereby a series of impulses will be produced when any of said key operated switches of said units is moved into circuit closing position and means for automatically retarding the movement of any of the switches of said key operated units into closing position while said make and break mechanism is in the circuit making position, in order toprevent the transmission of an incomplete signal.

12. In a semiautomatic telegraphic sending instrument, an electric circuit, a portable key operated unit including a switch, a constantly impelled circuit make and break mechanism constituting a separate unit and capable of acting continuously as a source of signals, electric connections between said constantly impelled make and break mechanism and said key operated switch, and means for automatically and temporarily retarding the operation of said key operated switch while said make and break mechanism is in the circuit making position, in order to prevent the transmission of an incomplete signal.

13. In a telegraph sending instrument, an electric circuit, a key operated circuit closing means, means for automatically controlling said circuit closing means, a constantly impelled automatic signal transmitter capable of producing uniformly timed electric signals, electric connections between said circuit closing means and said transmitter and means responsive to the operation of said transmitter and adapted to affect said automatic circuit control means so as to temporarily retard the closing of said circuit by said key operated closing means and thereby prevent the transmission of an incomplete signal.

14. In a semiautomatic telegraph sending instrument, an electric circuit, a key operated circuit closing means, a second circuit, an automatic circuit closing means therefor, said two circuit closing means being electrically connected in series with one another, an automatic constantly impelled signal transmitter capable of producing uniformly timed electric signals, electric connection between said transmitter and said key 0perated circuit closing means, and means affected by said second circuit and in its turn affecting said automatic circuit closing means, so as to temporarily retard the closing of said first circuit to prevent the transmission of an incomplete signal.

HORACE G. MARTIN. 

